Comparative analysis of the EEG in babies in the first month of life with gestation periods of 30-42 weeks.

The aim of the present work was to compare measures of the power spectra, indexes, and coherence of the EEG in term and preterm infants in the first month of life. Six groups of children were investigated, born at 1) 30-32, 2) 33-34, 3) 35-36, 4) 37-38, 5) 39-40, and 6) 41-42 weeks of gestation; there were 10 in each group. The power of the delta frequencies was maximal in group 5. The power of theta frequencies was greatest in group 3. The theta frequencies index was higher in groups 2, 3, and 4. Alpha frequency power was greater in group 2. The index of alpha frequencies was greater in groups 1, 2, and 3. The indexes of beta1 and beta2 frequencies was greater in groups 1, 2, and 4. The largest number of coherence links in the delta, theta, and alpha frequencies were seen in group 6. Group 2, as compared with group 5, had more coherence links in the delta frequencies in the posterior and posterocentral areas, as well as more intrahemisphere synchronization in the theta and alpha frequencies. The results obtained here showed that EEG power spectra, indexes, and coherence depended on the gestation age at the time of birth, though this relationship was nonlinear.

[Comparative analysis of the infant EEG at gestation term 30-42 weeks].

The research involved comparison of characteristics of the power spectrum, index, coherence of the EEG at preterm and full-term infants of the first month of life. 6 groups of children are surveyed: (1) 30-32, (2) 33-34, (3) 35-36, (4) 37-38, (5) 39-40, (6) 41-42 weeks of gestation; each group consisted of 10 children. Capacity of delta frequencies was high in the 5th group. Capacity of theta frequencies was high in the 3rd group. The index of theta frequencies was high in the 2nd, 3rd and 4th groups. Capacity of alpha frequencies was hagh in the 2nd group. The index of alpha frequencies was high in the 1st, 2nd and 3rd groups. Indexes and of beta1- and beta2-frequencies were higher in the 1st, 2nd and 4th groups. The maximum quantity of coherent delta, theta and alpha frequencies was in the 6th group. In the 2nd group, in comparison with 5th group, were more coherent delta frequencies in the occipital and occipital-central areas. The results obtained show that the spectrum of capacity, indexes and coherence of the EEG depend on term of gestation at the moment of birth but this dependence has nonlinear character.

[A correlation of EEG characteristics of pregnant women with the level of their anxiety].

It has been shown that the EEG of pregnant women with high anxiety level is characterized by a lower occipital alpha and theta rhythm spectral power if compared to the EEG of women with low anxiety level. The frequency of the alpha rhythm of their EEG was reliably higher. Pregnant women with high anxiety level with a pregnancy interruption threat diagnosis have an essentially lower occipital alpha rhythm spectral power than women of this group without such a diagnosis. And vice versa, the occipital alpha rhythm spectral power in the EEG of pregnant women with low anxiety level with a pregnancy interruption threat diagnosis is essentially higher and its frequency essentially lower than the EEG of women without that diagnosis. The data received are interpreted as a change in hormone regulation during the pregnancy period, as well as psychogenic influence on the pregnancy.

[Characteristics of the EEG power and coherent structure of term and premature children during the first postnatal year]. / Osobennosti spektra moshchnosti i kogerentnoi struktury EEG donoshennykh i nedonoshennykh detei na pervom mesiatse postnatal'nogo razvitiia.

Objective of the study involved characteristics of the spectre of the EEG power and coherent structure in children of different degree of maturity in the first month of their postnatal development. 32 children were divided into three groups: 1) 38-41 weeks (11 children); 2) 34-36 weeks (12 children); 3) 30-33 weeks (9 children). At the moment of the study the children's chronological age was as follows: in the 1st and 2nd groups--19 +/- 1, in the 3rd group--30 +/- 4 days. In the 1st group (mature children), a considerable power of delta- and theta-range frequencies was registered as compared with the 2nd and 3rd groups. In the 1st group children, a central gradient of power of the delta and theta frequencies was noted as well as a central-occipital one for alpha-frequencies. In the 2nd group (34-36 weeks), a lesser power of the delta-, theta- and alpha-frequencies was noted as well as a smoothed central gradient of these frequencies as compared with the 1st group. In the 3rd group, the power of delta-frequencies in frontal leads and power of alpha-frequencies in most EEG leads did not differ from those in the 1st group, and an obvious frontal gradient of delta-frequency power was noted as well as the frontal-central one for the theta- and alpha-frequencies. In all the groups, three foci of coherent interaction among the brain areas were registered: anterior, central and posterior. The coherence of biopotentials was registered on the frequencies of delta-, theta- and alpha-ranges. The maximum level of coherence was registered in the delta-range. In immature children, as compared with mature ones, a higher level of coherence was registered in the theta- and alpha-frequencies.

[Changes in anxiety level of Wistar rats under the influence of maximally-diluted solution of a plant alkaloid]. / Izmenenie urovnia trevozhnosti u krys linii Vistar pod vliianiem sverkhslabogo rastvora rastitel'nogo alkaloida.

A very dilute solution of Nux Vomica 200 plant alkaloid was applied onto the tongue of Wistar rats. The level of rats' anxiety was estimated by their behavior in elevated plus-maze. The dry application led to substantial changes in rats' behavior. In "passive" rats previously defined by the forced swimming tests changes in behavior were most prominent. The possible influence of the drug under study on the adaptive abilities of this group of animals is discussed.

[Postpartum borderline depressive states in women]. / Pogranichnye depressivnye sostoianiia u zhenshchin posle rodov.

The study aimed at determination of the structure of postpartum depressions in mothers and specification of the influence of some social and personality factors on their development. Nineteen mothers with borderline depression presented 3 types of depressive disorders: "maternity blues" syndrome, anxiety and agitated depression. All the women were exposed to special psychotherapeutic intervention. The differences were found between the study and control groups by social indices. The patients of the former one were featured by higher frequencies of first delivery and unregistered marriages, and their care-taking behavior bore formal character when mother fulfilled punctually all medical recommendations ignoring individual child's needs. Being evaluated according to A. Fogel et al, the types of mother-child interactions were determined as follows: reciprocal (symmetrical)--6 cases; unipolar (asymmetrical)--6 (maternal--3 and children--3); formal--6; disharmonic (uncoordinated)--1. The authors conclude that family aspect of psychotherapeutic effect is extremely important for the treatment of patients with postpartum borderline depressions.

[From physiological theory to psychological facts (on the centenary of I. P. Pavlov's speech in Madrid)]. / Ot fiziologicheskoi teorii k psikhologicheskim faktam (k 100-letiiu Madridskoi rechi I. P. Pavlova).

Pavlovian theory of conditioned reflexes and Ukhtomsky's theory of dominanta are considered as the most important biological concepts of the XX century. They have laid the foundation of the modern views of the adaptive and active character of the nervous activity underlying the integral behavior in the environment. Approach to a burning problem of neurophysiological mechanisms of goaldirected behavior is impossible without a comprehensive study of works of both these schools. They have formed not only the methodological basis of modern investigations but opened a new avenue of attack.

The effects of stages of the estrous cycle on pain thresholds in female white rats.

The effects of stages in the estrous cycle on electrical pain thresholds were studied in white rats in conditions of chronic measurement. On recording day 3, females in the diestrus and estrus stages showed sharp increases in shudder and paw-shuffling thresholds. Females in proestrus and metestrus showed no change in thresholds as compared with those in the first days of recording. Starting from day 7, there were progressive decreases in electrical pain thresholds regardless of the stage of the estrous cycle. Data for all animals showed that regular measurement of pain thresholds induces a smooth two-fold increase in body resistance from day 1 to day 7. This was followed by a sharp drop on day 8, with parallel decreases in body resistance and electrical pain thresholds. Thus, chronic measurement of electrical pain thresholds and body resistance changed in a complex fashion, and threshold values depended on the stage of the estrous cycle.

[Changes in spectral coherent characteristics of EEG in the early postpartum period in mothers with anxious and depressed mood]. / Izmeneniia spektral'no-kogerentnykh kharakteristik EEG v rannem poslerodovom periode u materei s trevozhno-depressivnym fonom nastroeniia.

Postpartum EEG spectral and coherence characteristics were estimated in mothers with or without postpartum depressions. In mothers without affective disorders the power of oscillations in the delta, theta, and alpha 1 frequency bands was increased as compared to controls. Intrahemispheric EEG coherence between the left frontal and adjacent derivations in the delta and theta bands and interhemispheric coherence in the central areas was increased and decreased over the remaining cortical surface. These changes led to a significant decrease in EEG asymmetry. It is suggested that during normal postpartum the influence of the limbicodiencephalic and lower brainstem structures on the cortex is augmented and a certain kind of dominanta is formed. In mothers with postpartum depressions the EEG alpha-band power was lower than in the control and normal groups, coherence changes in the delta and theta bands diminished the EEG asymmetry. The insufficiency of limbicodiencephalic influence and impairment of adaptive brainstem reactions are suggested to be responsible for problems in the formation of maternal dominanta, which results in the development of postpartum depressions.

The effects of prenatal stress on learning in rats in a Morris maze.

The offspring of female Wistar rats subjected to daily stress (they were placed in an unfamiliar social group for 1 h) during the last third of pregnancy were studied. The offspring of these females were tested for the ability to perform spatial orientation in a Morris water maze at the ages of two and four months. Prenatal stress had no effect on the ability of rats to learn in the Morris maze. However, two-month-old animals subjected to prenatal stress, unlike controls, demonstrated less flexibility in their behavioral strategy in solving the spatial orientation task. These animals were characterized by a clear tendency for their behavior to perseverate. By the age of four months, the differences between the control and prenatally stressed animals had disappeared.

[Changes in the neuroendocrine regulation of adaptive behavior in rats subjected to stress in the late prenatal ontogenesis]. / Izmenenie neiroéndokrinnoi reguliatsii prisposobitel'nogo povedeniia krys posle stressa v pozdnem prenatal'nom ontogeneze.

Female rats were subjected from the 14th to 17th day of pregnancy to immobilisation under conditions of 1-hour daily bright illumination. On the 20th day, contents of testosterone and estradiol was decreased with no sex difference in their level in the pregnant female rats' blood and in the amniotic fluid. Sex differences were flattened in 1-month litter both in the androgen and oestrogen contents and in adaptive behaviour. In prenatally stressed males, motor activity was inhibited and anxiety was enhanced as compared with the control. At one and a half months of age, the consequences of the prenatal stress disappeared and then reappeared after sexual maturation but with an opposite trend. Adaptive behaviour of adult males was less flexible and revealed no age-dependent oscillations inherent in the control animals. Prenatal stress while preventing the maximal raise of sex steroids in the blood shifts sex differentiation of the adaptive behaviour toward demasculinization.

[Effect of estrous cycle phase on pain threshold in female white rats]. / Vliianie stadii éstral'nogo tsikla na bolevye porogi samok belykh krys.

Pain thresholds and body resistance in female Wistar rats were determined during estrous cycle stages. The flinch and shuffle thresholds were increased on the 3rd day of measurement in diestrus and estrus but not in proestrus and metestrus as compared with the thresholds during the 1st day of recording. The thresholds decreased as of the 7th day to the 14th day. Daily threshold measurements raised the body resistance on the 7th day of recording. In contrast to the pain thresholds, the body resistance change had not a stage-dependent character.

[Cerebral mechanisms of behavior and higher mental functions]. / Mozgovye mekhanizmy povedeniia i vysshikh psikhicheskikh funktsii.

The paper is dedicated to the 50th anniversary of the Department of Higher Nervous Activity and Psychophysiology at St.-Petersburg State University.

[A. A. Ukhtomskii and I. P. Pavlov: a controversy or a dialogue?]. / A. A. Ukhtomskii i I. P. Pavlov: spor ili dialog?

Pavlov's concept of conditioned reflexes and Ukhtomskii theory of dominanta fall within the biological line in physiology. They unravel the integral adaptive and active nature of the organism behavior in the environment. It is impossible to develop modern concepts about the determinants of goal-directed behavior of animals and voluntary activity of humans without in-depth study of the achievements of these Russian physiological schools which not only formed the methodological basis for the current studies but also directed the way for their further development.